I've created a few rules with CiviRules that trigger an email. They all work perfectly as long as I don't add a delay.
I've tested adding a 1-minute delay with different types of rules but the email never gets triggered?

The job appears in the civicrm_queue_item table but doesn't get released

The job log for CiviRules delayed actions says success

Using CiviCRM 4.7.27 and CiviRules 1.15

I did further testing on my local environment and it works as expected when I changed the site's timezone to the one I live in.

Update: The emails were sent in the end but 11 hrs later even though the release date was correctly set to 1 minute later in the civicrm_queue_item table